



 
Gerry, You can use our volume calculator tool. Go to the Quandaries and Queries page on Math Central and follow the link to Volume calculator.Use this tool to find the volume of the hole (8 inches in diameter by 5 feet deep) and then the volume of the section of the post in the hole (4 inches by 4 inches by 5 feet). The difference is the volume of stonedust you will need in each hole. Multiply by 30 to obtain the total volume needed. Cheers,  


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